KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 5 of 5

Some of the metrics are blocked by your
consent settings
Intelligent photovoltaic farms for robust frequency stabilization in multi-area interconnected power system based on PSO-based optimal Sugeno fuzzy logic control
(2015-02-01)
Sa-ngawong, Nattapol
;
Ngamroo, Issarachai
Currently, the grid-connected large PV farms are extensively installed in power systems. Nevertheless, in addition to the load change, the intermittent power output of PV farms may lead to the serious problem of the system frequency fluctuation. To handle this problem, this paper proposes a new design of Sugeno fuzzy logic controller based on particle swarm optimization (PSO-SFLC) of intelligent PV farms for the frequency stabilization in a multi-area interconnected power system. To handle various scenarios, the frequency deviations and solar insolations are used as input signals of the PSO-SFLC. The output signal of the PSO-SFLC is a command signal for adjusting PV output power. The output power of PV is controlled by the PSO-SFLC to meet the load demand so that the system frequency fluctuation can be suppressed. Without the difficulty of trial and error, the optimal input and output membership functions, and control rules of PSO-SFLC are automatically achieved by PSO. Simulation study in a three-area loop interconnected power system with large PV farms elucidates that the frequency stabilizing performance and robustness of the PV equipped with the PSO-SFLC is much superior to that of the PV with the SFLC and the PV with the maximum power point tracking control in scenarios with various solar insolations and loading conditions.
Some of the metrics are blocked by your
consent settings
Overlapping decompositions-based robust decentralized tabu search-optimized fixed structure H∞ frequency stabilizer design in interconnected power systems
(2013-07-17)
Ngamroo, Issarachai
As interconnected power systems are subjected to load disturbances with changing frequency in the vicinity of the inter-area oscillation mode, the system frequency may severely oscillate. To stabilize frequency oscillation, the dynamic power flow control devices can be exploited. This paper focuses on a new robust decentralized fixed structure H<inf>∞</inf> frequency stabilizer design of power control devices based on overlapping decompositions. The tie-line between two interconnected systems can be treated as the overlapped variable so that the original system can be decomposed into two subsystems. The frequency stabilizer equipped with the power control device can be designed in each subsystem independently. The structure of frequency stabilizer is specified as the 2<sup>nd</sup>-order lead/lag compensator. To augment the system robust stability, the multiplicative uncertainty is employed to represent all unstructured system uncertainties. As a result, the multiplicative stability margin (MSM) can be used to guarantee the system robust stability. The control parameters of frequency stabilizer are optimized by a tabu search, so that the desired damping ratio of the target inter-area mode and the highest MSM are achieved. Two examples of power flow devices, i.e., high-voltage direct current transmission system and superconducting magnetic energy storage, are used to show the high performance and robustness against load disturbances and system parameters variation. © 2013 ICIC International.
Some of the metrics are blocked by your
consent settings
PSO-based Sugeno fuzzy logic controller of photovoltaic generator for frequency stabilization in stand-alone power system
(2013-01-01)
Sa-Ngawong, Nattapol
;
Ngamroo, Issarachai
This paper proposes a particle swarm optimization-based Sugeno fuzzy logic controller (PSO-SFLC) of photovoltaic (PV) generator for frequency stabilization in a stand-alone power system. The PSO-SFLC is used to adjust the modulation ratio of the PV inverter so that the PV output power can be swiftly controlled to follow the load change and stabilize the system frequency fluctuation. The PSO is used to automatically tune membership functions and control rules of SFLC. The input signals of SFLC are solar insolation and frequency deviation signals while the output signal is the modulation ratio of the inverter. In the simulation study, the frequency stabilizing effect of PV with PSO-SFLC is compared with the PV with SFLC and the PV with maximum power point tracking under random load and solar insolation change. Simulation results show the superior effect of the PV with proposed PSO-SFLC over the PV with SFLC and the PV with maximum power point tracking. © 2013 IEEE.
Some of the metrics are blocked by your
consent settings
Robust controller design of microturbine and electrolyzer for frequency stabilization in a microgrid system with plug-in hybrid electric vehicles
(2012-12-01)
Vachirasricirikul, Sitthidet
;
Ngamroo, Issarachai
This paper proposes a new robust controller design of microturbine (MT) and electrolyzer (ES) in a control and monitoring system (CMS) for frequency stabilization in a microgrid system with plug-in hybrid electric vehicles (PHEVs). In the studied microgrid, the MT is normally used to provide the main power to the loads while the ES absorbs the power from the system to produce the hydrogen as the fuel input for the power generation of the fuel cell. On the other hand, the large numbers of PHEVs are utilized in the consumer side. The concurrent charging powers of PHEVs cause a problem of severe frequency fluctuation in the microgrid. To solve this problem, the frequency stabilization of CMS is performed by controlling the power output of MT and ES. The controller structure of MT and ES is a proportional integral with a single input. To enhance the tracking performance and the robustness against system uncertainties of the designed MT and ES controllers, the control parameters are optimized by shuffled frog leaping algorithm based on specified-structure mixed H <inf>2</inf>/H <inf>∞</inf> control technique. Simulation results not only show the frequency stabilization effect against the random charging power of PHEVs but also the high robustness of the proposed robust MT and ES controllers against the system parameters variation. © 2012 Elsevier Ltd. All rights reserved.
Some of the metrics are blocked by your
consent settings
Application of electrolyzer system to enhance frequency stabilization effect of microturbine in a microgrid system
(2009-09-01)
Vachirasricirikul, Sitthidet
;
Ngamroo, Issarachai
;
Kaitwanidvilai, Somyot
It is well known that the power output of microturbine can be controlled to compensate for load change and alleviate the system frequency fluctuations. Nevertheless, the microturbine may not adequately compensate rapid load change due to its slow dynamic response. Moreover, when the intermittent power generations from wind power and photovoltaic are integrated into the system, they may cause severe frequency fluctuation. In order to study the fast dynamic response, this paper applies electrolyzer system to absorb these power fluctuations and enhance the frequency control effect of microturbine in the microgrid system. The robust coordinated controller of electrolyzer and microturbine for frequency stabilization is designed based on a fixed-structure H<inf>∞</inf> loop shaping control. Simulation results exhibit the robustness and stabilizing effects of the proposed coordinated electrolyzer and microturbine controllers against system parameters variation and various operating conditions. Crown Copyright © 2009.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results